Purchase this article with an account.
N. A. Delamere, R. M. Pelis, M. Shahidullah; Distribution of Transporters in the Porcine Ciliary Epithelium. Invest. Ophthalmol. Vis. Sci. 2009;50(13):1449.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Aqueous humor secretion is the result of net ion transport by the ciliary epithelium bilayer. The process is thought to involve the coordinated operation of basolateral transporters and channels in the pigmented (PE) and nonpigmented (NPE) cell layers. Here studies were conducted in an attempt to confirm the localization of several transporters. Unexpectedly, some transporters were found to have an apical location.
Immunolocalization experiments were carried out on porcine eyes and cultured porcine NPE.
Na,K-ATPase and the sodium-proton exchanger NHE1 were detected basolaterally in both PE and NPE. Both transporters appeared more abundant in the NPE. The xenobiotic transporter MRP2 was detected at the junction between the apical surfaces of the NPE and PE, not at the basolateral surface of either cell type. The sodium-potassium-chloride cotransporter NKCC also was observed apically, at the junction between the NPE and PE. Both NKCC and MRP2 were detected in porcine NPE grown in primary culture.
The findings are consistent with expression of transporters NKCC and MRP2 at the apical surface of NPE. Solute transporters in the ciliary epithelium bilayer may not be located exclusively on the basolateral surfaces of the NPE and PE layers. Further studies are required to determine whether apical transporters shift solutes between the ciliary process stroma and NPE, bypassing the PE.
This PDF is available to Subscribers Only